In-wheel working device

ABSTRACT

An in-wheel working device including: a stator fixed to the inside of a housing, a rotor rotatably installed in the stator, a rotating part rotatably installed in the housing, and rotated with the rotor, a resolver fixing part fixed to the inside of the housing, and a resolver moving part. The resolver moving part includes a resolver rotor positioned outside the resolver fixing part and facing the resolver fixing part, and a cover part fixed to the rotating part and covering the resolver rotor.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims priority from and the benefit of Korean PatentApplication No. 10-2017-0090813, filed on Jul. 18, 2017, and KoreanPatent Application No. 10-2018-0069974, filed on Jun. 19, 2018, whichare hereby incorporated by reference for all purposes as if set forthherein.

BACKGROUND Field

Exemplary embodiments relate to an in-wheel working device, and moreparticularly, to an in-wheel working device which can secure a space forinstalling a gear shift in a rotor by changing a structure for measuringrotation of a motor.

Discussion of the Background

The exhaustion of fossil fuels has promoted the development of electricvehicles which drive a motor using electric energy stored in a battery,instead of vehicles using the fossil fuels such as gasoline and diesel.

Electric vehicles may be divided into a pure electric vehicle thatdrives a motor using only electric energy stored in a rechargeablebattery, a solar cell vehicle that drives a motor using a photoelectriccell, a fuel cell vehicle that drives a motor using a fuel cell based onhydrogen fuel, and a hybrid vehicle that uses an engine and motortogether by driving the engine using fossil fuel and driving the motorusing electricity.

In general, an in-wheel working device is a technique used for avehicle, such as an electric vehicle, which uses electricity as a powersource. Unlike a system that rotationally drives wheels using powertransferred through an engine, transmission, and drive shaft of agasoline or diesel vehicle, the in-wheel working device directlytransfers power to the wheels using motors arranged in left and rightdrive wheels or four left/right and front/rear drive wheels.

Since a resolver for measuring rotation of the motor in the conventionalin-wheel working device is installed on a rotating shaft of the motor,the size of the in-wheel working device is increased, which makes itdifficult to additionally install a gear shift in a rotor. In this case,the power of the vehicle may be reduced. Therefore, there is a demandfor a device capable of solving the problem.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention and,therefore, it may contain information that does not constitute priorart.

SUMMARY

Exemplary embodiments of the invention are directed to an in-wheelworking device which can secure a space for installing a gear shift in arotor by changing a structure for measuring rotation of a motor, therebyimproving mounting compatibility and power.

An exemplary embodiment of the invention provides an in-wheel workingdevice including: a stator fixed to the inside of a housing; a rotorrotatably installed in the stator; a rotating part rotatably installedin the housing, and rotated with the rotor; a resolver fixing part fixedto the inside of the housing; and a resolver moving part. The resolvermoving part includes a resolver rotor positioned outside the resolverfixing part facing the resolver fixing part, and a cover part fixed tothe rotating part and covering the resolver rotor.

The cover part may be injection-molded in a shape to cover the resolverrotor.

The rotating part may include a mounting frame installed in a shape tocover the rotor; and a motor shaft connected to the mounting frame,having a hollow portion formed therein, and rotatably installed in thehousing.

The cover part may have a larger inner diameter than the outer diameterof the resolver fixing part, and fixed to the mounting frame.

The in-wheel working device may further include: a gear shift partconfigured to shift gears using power received from the motor shaft; anda drive shaft formed in a shaft shape passing through the inside of themotor shaft, and rotated by power received from the gear shift part.

The cover part may include a first cover installed in a shape to coverone side of the resolver rotor; and a second cover installed in a shapeto cover the other side of the resolver rotor.

The first cover may include a first base forming a plane in a circulararc shape at a position facing the one side of the resolver rotor; afirst inner member extended from the inner circumference of the firstbase toward the second cover; and a first outer member extended from theouter circumference of the first base toward the second cover.

The second cover may include a second base forming a plane in a circulararc shape at a position facing the other side of the resolver rotor; asecond inner member extended from the inner circumference of the secondbase toward the first cover; and a second outer member extended from theouter circumference of the second base toward the first cover.

Another exemplary embodiment of the invention provides an in-wheelworking device including: a stator fixed to the inside of a housing; arotor rotatably installed in the stator; a rotating part rotatablyinstalled in the housing, and rotated with the rotor; a resolver fixingpart fixed to the inside of the housing; and a resolver rotor positionedoutside the resolver fixing part facing the resolver fixing part. Theresolver rotor is fixed to the rotating part, rotated with the rotatingpart, and implemented with a single member.

The resolver rotor may include a rotor body forming a plane in a beltshape along a circular arc shape; and an inner groove forming apolygonal groove in the rotor body.

The rotating part may include a mounting frame installed in a shape tocover the rotor; and a motor shaft connected to the mounting frame,having a hollow portion formed therein, and rotatably installed in thehousing.

The rotor body may be fixed to the mounting frame by a fastening member.

The rotor body may have a plurality of mounting grooves formed along theouter circumference thereof, and the mounting grooves directly mountedon the mounting frame.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention.

FIG. 1 schematically illustrates the structure of an in-wheel workingdevice in accordance with a first embodiment of the present invention.

FIG. 2 illustrates an installation state of a resolver moving part and aresolver fixing part in accordance with the first embodiment of thepresent invention.

FIG. 3 illustrates the resolver moving part and the resolver fixing partin accordance with the first embodiment of the present invention.

FIG. 4 schematically illustrates the structure of an in-wheel workingdevice in accordance with a second embodiment of the present invention.

FIG. 5 is an exploded perspective view of a resolver moving part inaccordance with the second embodiment of the present invention.

FIG. 6 is an assembled perspective view of the resolver moving part inaccordance with the second embodiment of the present invention.

FIG. 7 is a perspective view illustrating that a resolver rotor inaccordance with the present embodiment has fastening holes formedtherein.

FIG. 8 is a perspective view illustrating that a resolver rotor inaccordance with another embodiment of the present invention has mountinggrooves.

DETAILED DESCRIPTION

The invention is described more fully hereinafter with reference to theaccompanying drawings, in which exemplary embodiments of the inventionare shown. This invention may, however, be embodied in many differentforms and should not be construed as limited to the exemplaryembodiments set forth herein. Rather, these exemplary embodiments areprovided so that this disclosure is thorough, and will fully convey thescope of the invention to those skilled in the art. In the drawings, thesize and relative sizes of layers and regions may be exaggerated forclarity. Like reference numerals in the drawings denote like elements.

It will be understood that for purposes of this disclosure, “at leastone of X, Y, and Z” can be construed as X only, Y only, Z only, or anycombination of two or more items X, Y, and Z (e.g., XYZ, XYY, YZ, ZZ).Unless particularly described to the contrary, the term “comprise”,“configure”, “have”, or the like, which are described herein, will beunderstood to imply the inclusion of the stated components, andtherefore should be construed as including other components, and not theexclusion of any other elements.

Hereafter, an in-wheel working device in accordance with an exemplaryembodiment of the invention will be described in detail with referenceto the accompanying drawings. It should be noted that the drawings arenot to precise scale and may be exaggerated in thickness of lines orsizes of components for descriptive convenience and clarity only.

Furthermore, the terms as used herein are defined by taking functions ofthe invention into account and can be changed according to the custom orintention of users or operators. Therefore, definition of the termsshould be made according to the overall disclosures set forth herein.

FIG. 1 schematically illustrates the structure of an in-wheel workingdevice in accordance with a first embodiment of the present invention,FIG. 2 illustrates an installation state of a resolver moving part and aresolver fixing part in accordance with the first embodiment of thepresent invention, and FIG. 3 illustrates the resolver moving part andthe resolver fixing part in accordance with the first embodiment of thepresent invention.

As illustrated in FIGS. 1 to 3, the in-wheel working device 1 inaccordance with the embodiment of the present invention may include astator 20 fixed to the inside of a housing 10, a rotor 30 rotatablyinstalled in the stator 20, a rotating part 40 rotatably installed inthe housing 10 and rotated with the rotor 30, a resolver moving part 50fixed to the rotating part 40 and rotated with the rotating part 40, anda resolver fixing part 90 fixed to the inside of the housing 10 facingthe resolver moving part 50.

The housing 10 forming the exterior of the in-wheel working device 1 maybe fixed to a vehicle body, and the stator 20, the rotor 30, therotating part 40, the resolver moving part 50, the resolver fixing part90, a gear shift part 100, a drive shaft 110 and a hub part 120 may beinstalled in the housing 10.

The stator 20 may be formed in a ring shape, and fixed to the inside ofthe housing 10. The stator 20 may have coil members 22 installed at thetop and bottom thereof, respectively, and the rotations of the stator 20and the coil member 22 may be constrained.

The rotor 30 may be rotatably installed in the stator 20, and rotatedaccording to flux changes of the stator 20 and the coil member 22. Therotor 30 may be formed in a ring shape, and have a magnetic force. Sincethe detailed configurations and operations of the stator 20 and therotor 30 are publicly known, the detailed descriptions thereof areomitted herein.

The rotating part 40 may be formed in various shapes, as long as therotating part 40 can be rotatably installed in the housing 10 androtated with the rotor 30. The rotating part 40 in accordance with thepresent embodiment may include a mounting frame 42 and a motor shaft 44.The mounting frame 42 may be formed in a plate shape which is brought incontact with one side surface and the top and bottom surfaces of therotor 30 with a rectangular cross-section, and connected to the rotor 30so as to rotate with the rotor 30. The mounting frame 42 may have aprotrusion formed at the top thereof, and the resolver moving part 50may be fixed to the protrusion. Therefore, the rotating part 40, therotor 30 and the resolver moving part 50 may be rotated together.

The motor shaft 44 may be connected to the mounting frame 42 and rotatedwith the mounting frame 42. Furthermore, the motor shaft 44 may berotatably installed in the housing 10, and have a hollow portion formedtherein. The motor shaft 44 may be extended in the top-to-bottomdirection, the gear shift part 100 may be installed at one side of themotor shaft 44, and the hub part 120 may be installed at the other sideof the motor shaft 44.

The resolver moving part 50 may be fixed to the rotating part 40, androtated with the rotating part 40. The resolver moving part 50 inaccordance with the present embodiment may include a cover part 52 and aresolver rotor 51.

The cover part 52 may be formed through injection molding, fixed to themounting frame 42, and have a larger inner diameter than the outerdiameter of the resolver fixing part 90. The resolver rotor 51 may befixed to the cover part 52, and positioned outside the resolver fixingpart 90. Since the cover part 52 formed of synthetic resin isinjection-molded in a shape to cover the resolver rotor 51, the resolverrotor 51 and the cover part 52 may be coupled as one body. Furthermore,since the cover part 52 is fixed to the outside of the mounting frame42, the resolver moving part 50 may be rotated with the rotating part40.

The resolver fixing part 90 may be fixed to the inside of the housing 10facing the resolver moving part 50. Each of the resolver rotor 51 andthe resolver fixing part 90 may have a two-phase winding, and detect theangular velocity and angular position of the rotating part 40 through achange of an output voltage value. For example, the coil of the resolverfixing part 90 may be wound in such a manner that flux distributionbecomes a sine wave with respect to an angle. When the rotor 30 isrotated after an excitation voltage is applied to the primary coilcorresponding to an input side, a voltage may be generated at thesecondary coil corresponding to an output side while a magnetic couplingcoefficient is changed. The coil of the resolver fixing part 90 may bewound in such a manner that the voltage is changed to the sine andcosine of the rotation angle of the rotor 30. The amplitude ratio of thesine output to the cosine output may be determined in order to recognizethe rotation angle and position of the rotor 30. In addition, variousresolver measurement techniques can be applied in order to measure theangular position and angle of the rotor 30.

The resolver fixing part 90 may be formed in a ring shape and fixed tothe inside of the housing 10, the inside of the resolver rotor 51positioned outside the resolver fixing part 90 may form a polygonalgroove, and the outside of the resolver rotor 51 may form a circularcurved surface. The cover part 52 may have a larger outer diameter thanthe outer diameter of the resolver rotor 51, and injection-molded withthe resolver rotor 51.

In order to reduce noise caused by the motor including the stator 20 andthe rotor 30, the cover part 52 may be mounted outside the resolverrotor 51. Since the resolver moving part 50 is installed at the top ofthe rotor 30 or adjacent to the coil member 22, noise is highly likelyto be generated by an electromagnetic force generated by the rotor 30and the stator 20. Thus, the cover part 52 may be installed to cover theresolver rotor 51, such that a space for isolating the resolver rotor 51from the rotor 30 can be secured while the electromagnetic force of thestator 20 and the rotor 30 is reduced. Therefore, noise can be reduced.

The in-wheel working device 1 in accordance with the embodiment of thepresent invention may further include the gear shift part 100, the driveshaft 110 and the hub part 120. The gear shift part 100 may includevarious types of gear shift devices, as long as the gear shift part 100can shift gears using power received from the motor shaft 44. The gearshift part 100 in accordance with the embodiment of the presentinvention may include a sun gear 102, a planetary gear 104, a carrier106 and a ring gear 108.

The sun gear 102 may be connected to the top of the motor shaft 44, andhave gear teeth formed outside a pipe-shaped body thereof. Therefore,the sun gear 102 may be rotated with the motor shaft 44. The planetarygear 104 may be installed outside the sun gear 102, and the carrier 106may rotatably support the planetary gear 104. The ring gear 108positioned outside the carrier 106 may maintain a fixed state.

Since the carrier 106 is connected to the drive shaft 110, power reducedthrough the carrier 106 may be outputted through the drive shaft 110.

The drive shaft 110 may be formed in a shaft shape which passes throughthe inside of the motor shaft 44, and rotated by power received from thegear shift part 100. The top of the drive shaft 110 extended in thetop-to-bottom direction may be connected to the carrier 106, and thebottom of the drive shaft 110 may be connected to a hub inner race 122of the hub part 120 so as to receive rotation power.

The hub part 120 may include the hub inner race 122, a hub outer race124 and a hub bearing 126. The hub inner race 122 may be spline-coupledto the drive shaft 110, and rotated with the drive shaft 110, the hubouter race 124 may be positioned outside the hub inner race 122, and thehub bearing 126 may be positioned between the hub inner race 122 and thehub outer race 124. The wheel of the vehicle may be rotated by therotation of the hub inner race 122.

Hereafter, the operation state of the in-wheel working device 1 inaccordance with the embodiment of the present invention will bedescribed in detail with reference to the accompanying drawings.

The mounting frame 42 and the motor shaft 44 which constitute therotating part 40 may be rotated by the rotation of the rotor 30. At thistime, the cover part 52 and the resolver rotor 51 of the resolver movingpart 50 fixed to the mounting frame 42 may also be rotated. Therefore,the resolver fixing part 90 may measure the angular velocity and angularposition of the resolver moving part 50, in order to recognize theangular velocity and angular position of the rotor 30. Since theresolver moving part 50 and the resolver fixing part 90 which constitutethe resolver are positioned at the top of the rotor 30, the gear shiftpart 100 can be installed at the top of the motor shaft 44 while anincrease of the size is minimized.

The sun gear 102 may be rotated by the rotation of the motor shaft 44,and the carrier 106 supporting the planetary gear 104 may be rotatedwhile the velocity thereof is reduced. The drive shaft 110 connected tothe carrier 106 may transfer power to the spline-coupled hub inner race122, and the wheel of the vehicle may be rotated by the rotation of thehub inner race 122.

In accordance with the embodiment of the present invention, since theresolver moving part 50 and the resolver fixing part 90 for measuringthe rotation of the rotor 30 are installed in the stator 20, theinstallation space of the gear shift part 100 for changing the output ofthe rotating part 40 can be secured, which makes it possible to improvethe power of the vehicle.

FIG. 4 schematically illustrates the structure of an in-wheel workingdevice in accordance with a second embodiment of the present invention,FIG. 5 is an exploded perspective view of a resolver moving part inaccordance with the second embodiment of the present invention, and FIG.6 is an assembled perspective view of the resolver moving part inaccordance with the second embodiment of the present invention.

As illustrated in FIGS. 4 to 6, the in-wheel working device 1 inaccordance with the second embodiment of the present invention mayinclude a stator 20 fixed to the inside of a housing 10, a rotor 30rotatably installed in the stator 20, a rotating part 40 rotatablyinstalled in the housing 10 and rotated with the rotor 30, a resolvermoving part 50 fixed to the rotating part 40, rotated with the rotatingpart 40, and implemented by a plurality of members, and a resolverfixing part 90 fixed to the inside of the housing 10 facing the resolvermoving part 50.

The housing 10 forming the exterior of the in-wheel working device 1 maybe fixed to the vehicle body, and the stator 20, the rotor 30, therotating part 40, the resolver moving part 50, the resolver fixing part90, a gear shift part 100, a drive shaft 110 and a hub part 120 may beinstalled in the housing 10.

The stator 20 may be formed in a ring shape, and fixed in the housing10. The stator 20 may have coil members 22 installed at the top andbottom thereof, and the stator 20 and the coil members 22 may beconstrained from rotating.

The rotor 30 may be rotatably installed in the stator 20, and rotatedaccording to flux changes of the stator 20 and the coil member 22. Therotor 30 may be formed in a ring shape, and have a magnetic force. Sincethe detailed configurations and operations of the stator 20 and therotor 30 are publicly known, the detailed descriptions thereof areomitted herein.

The rotating part 40 may be formed in various shapes, as long as therotating part 40 can be rotatably installed in the housing 10 androtated with the rotor 30. The rotating part 40 in accordance with thesecond embodiment may include a mounting frame 42 and a motor shaft 44.The mounting frame 42 may be formed in a plate shape which is brought incontact with one side surface and the top and bottom surfaces of therotor 30, and the rotor 30 may be connected to the mounting frame 42 androtated with the mounting frame 42.

The mounting frame 42 may have a protrusion formed at the top thereof,and the resolver moving part 50 may be fixed to the protrusion.Therefore, the rotating part 40, the rotor 30 and the resolver movingpart 50 may be rotated together.

The motor shaft 44 may be connected to the mounting frame 42 and rotatedwith the mounting frame 42. Furthermore, the motor shaft 44 may berotatably installed in the housing 10, and have a hollow portion formedtherein. The motor shaft 44 may be extended in the top-to-bottomdirection, the gear shift part 100 may be installed at one side of themotor shaft 44, and the hub part 120 may be installed at the other sideof the motor shaft 44.

The resolver moving part 50 may be fixed to the rotating part 40, androtated with the rotating part 40. The resolver moving part 50 inaccordance with the second embodiment may include a resolver rotor 51and a cover part 52. The cover part 52 may include a first cover 53 anda second cover 56.

The resolver rotor 51 may be formed in a ring shape and positionedoutside the resolver fixing part 90, the inside of the resolver rotor 51may form a polygonal groove, and the outside of the resolver rotor 51may form a circular curved surface.

The first cover 53 may be installed in a shape to cover one side of theresolver rotor 51, and the second cover 56 may be installed in a shapeto cover the other side of the resolver rotor 51. The first and secondcovers 53 and 56 may be injection-molded separately from the resolverrotor 51, and then coupled to the resolver rotor 51 so as to form anassembly. The resolver rotor 51 may be used in common, and the first andsecond covers 53 and 56 may be manufactured in a package shape andcoupled to the resolver rotor 51, which makes it possible to remove aproblem that the manufacturing cost is increased by a model change.

The first and second covers 53 and 56 may be formed through injectionmolding, fixed to the mounting frame 42, and have a larger innerdiameter than the outer diameter of the resolver fixing part 90. Theresolver rotor 51 may be positioned between the first and second covers53 and 56. The first and second covers 53 and 56 may be formed ofsynthetic resin, injection-molded separately from the resolver rotor 51,and installed in a shape to cover the resolver rotor 51. Furthermore,since the first and second covers 53 and 56 are fixed to the outside ofthe mounting frame 42, the resolver moving part 50 may be rotated withthe rotating part 40.

The first cover 53 in accordance with the second embodiment may includea first base 54, a plurality of first inner members 55A and a firstouter member 55B. The first base 54 may form a plane in a circular arcshape at a position facing the one side of the resolver rotor 51.

The first inner members 55A may be extended from the inner circumferenceof the first base 54 toward the second cover 56. The first inner members55A may be installed along the inner circumference of the first base 54so as to be spaced at preset intervals.

The first outer member 55B may be extended from the outer circumferenceof the first base 54 toward the second cover 56. Between the first innermembers 55A and the first outer member 55B, a groove for seating theresolver rotor 51 may be formed. The first outer member 55B may beextended in a ring shape while having a level difference from the firstbase 54.

The second cover 56 in accordance with the second embodiment may includea second base 57, a plurality of second inner members 58A and a secondouter member 58B. The second base 57 may form a plane in a circular arcshape at a position facing the other side of the resolver rotor 51.

The second inner members 58A may be extended from the innercircumference of the second base 57 toward the first cover 53. Thesecond inner members 58A may be installed along the inner circumferenceof the second base 57 so as to be spaced at preset intervals.

The second outer member 58B may be extended from the outer circumferenceof the second base 57 toward the first cover 53. Between the secondinner members 58A and the second outer member 58B, a groove for seatingthe resolver rotor 51 may be formed. The second outer member 58B may beextended in a ring shape while having a level difference from the secondbase 57.

With the resolver rotor 51 positioned between the first and secondcovers 53 and 56, the first inner member 54 may be brought in contactwith the second inner member 58A and constrained from moving, and thefirst outer member 55B may also be brought in contact with the secondouter member 58B and constrained from moving. The first and secondcovers 53 and 56 may be fixed through a bolt or adhesive. Alternatively,the first and second covers 53 and 56 may be fixed to each other throughvarious coupling methods such as laser welding and thermal welding.

In order to reduce noise caused by the motor including the stator 20 andthe rotor 30, the first and second covers 53 and 56 may be mounted onthe outside of the resolver rotor 51. Since the resolver moving part 50is installed at the top of the rotor 30 or adjacent to the coil member22, noise is likely to be caused by an electromagnetic force generatedby the rotor 30 and the stator 20. Therefore, the first and secondcovers 53 and 56 may be installed to cover the resolver rotor 51, suchthat a space for isolating the resolver rotor 51 from the rotor 30 canbe secured while reducing the electromagnetic force of the stator 20 andthe rotor 30, transferred to the resolver rotor 51. Thus, noise can bereduced.

The resolver fixing part 90 may be fixed to the inside of the housing 10facing the resolver moving part 50. Each of the resolver rotor 51 andthe resolver fixing part 90 may have a two-phase winding, and detect anangular velocity and angular position of the rotating part 40 through achange of an output voltage. For example, the coil of the resolverfixing part 90 may be wound in such a manner that flux distributionbecomes a sine wave with respect to an angle. When the rotor 30 isrotated after an excitation voltage is applied to the primary coilcorresponding to an input side, a voltage may be generated at thesecondary coil corresponding to an output side while a magnetic couplingcoefficient is changed. The coil of the resolver fixing part 90 may bewound in such a manner that the voltage is changed to the sine andcosine of the rotation angle of the rotor 30. The amplitude ratio of thesine output to the cosine output may be determined in order to recognizethe rotation angle and position of the rotor 30. In addition, variousresolver measurement techniques can be applied in order to measure therotation position and angle of the rotor 30. Since the resolver fixingpart 90 in accordance with the second embodiment is formed in a ringshape and fixed to the inside of the housing 10, the rotation of theresolver fixing part 90 may be constrained.

The in-wheel working device 1 in accordance with the second embodimentof the present invention may further include the gear shift part 100,the drive shaft 110 and the hub part 120. The gear shift part 100 mayinclude various types of gear shift devices, as long as the gear shiftpart 100 can shift gears using power received from the motor shaft 44.The gear shift part 100 in accordance with the second embodiment mayinclude a sun gear 102, a planetary gear 104, a carrier 106 and a ringgear 108.

The sun gear 102 may be connected to the top of the motor shaft 44, andhave gear teeth formed on the outside of the pipe-shaped body thereof.Therefore, the sun gear 102 may be rotated with the motor shaft 44. Theplanetary gear 104 may be installed outside the sun gear 102, and thecarrier 106 may rotatably support the planetary gear 104. The ring gear108 positioned outside the carrier 106 may maintain a fixed state.

Since the carrier 106 is connected to the drive shaft 110, power reducedthrough the carrier 106 may be outputted through the drive shaft 110.

The drive shaft 110 may be formed in a shaft shape which passes throughthe inside of the motor shaft 44, and rotated by power received from thegear shift part 100. The top of the drive shaft 110 extended in thetop-to-bottom direction may be connected to the carrier 106, and thebottom of the drive shaft 110 may be connected to a hub inner race 122of the hub part 120 so as to receive rotation power.

The hub part 120 may include the hub inner race 122, a hub outer race124 and a hub bearing 126. The hub inner race 122 may be spline-coupledto the drive shaft 110 and rotated with the drive shaft 110, the hubouter race 124 may be positioned outside the hub inner race 122, and thehub bearing 126 may be positioned between the hub inner race 122 and thehub outer race 124. The wheels of the vehicle may be rotated by therotation of the hub inner race 122.

Hereafter, the operation state of the in-wheel working device 1 inaccordance with the second embodiment of the present invention will bedescribed in detail with reference to the accompanying drawings.

The mounting frame 42 and the motor shaft 44 which constitute therotating part 40 may be rotated by the rotation of the rotor 30. At thistime, the first and second covers 53 and 56 and the resolver rotor 2 ofthe resolver moving part 50 fixed to the mounting frame 42 may also berotated. Therefore, the resolver fixing part 90 may measure the angularvelocity and angular position of the resolver moving part 50, in orderto recognize the angular velocity and angular position of the rotor 30.Since the resolver moving part 50 and the resolver fixing part 90 whichconstitute the resolver are positioned at the top of the rotor 30, thegear shift part 100 may be installed at the top of the motor shaft 44while an increase of the size is minimized.

The sun gear 102 may be rotated by the rotation of the motor shaft 44,and the carrier 106 supporting the planetary gear 104 may be rotatedwhile the velocity thereof is reduced. The drive shaft 110 connected tothe carrier 106 may transfer power to the spline-coupled hub inner race122, and the wheels of the vehicle may be rotated by the rotation of thehub inner race 122.

Even when the model is changed, the resolver rotor 51 can be used incommon, and only the first and second covers 53 and 56 may be separatelymanufactured, which makes it possible to save the manufacturing cost anddistribution cost. Furthermore, only the first and second covers 53 and56 may be separately manufactured and applied to a package, and variousassembly structures can be applied depending to the shapes of the firstand second covers 53 and 56.

Hereafter, an in-wheel working device 1 in accordance with anotherembodiment of the present invention will be described with reference tothe drawings.

For convenience of description, components which are configured andoperated in the same manner as those of the second embodiment arerepresented by like reference numerals, and the detailed descriptionsthereof are omitted herein.

FIG. 7 is a perspective view illustrating that a resolver rotor inaccordance with the present embodiment has fastening holes formedtherein.

As illustrated in FIGS. 4 to 7, the in-wheel working device 1 inaccordance with the present embodiment may include a stator 20 fixed tothe inside of a housing 10, a rotor 30 rotatably installed in the stator20, a rotating part 40 rotatably installed in the housing 10 and rotatedwith the rotor 30, a resolver rotor 51 fixed to the rotating part 40,rotated with the rotating part 40, and implemented with a single member,and a resolver fixing part 90 fixed to the inside of the housing 10facing the resolver rotor 51.

The resolver rotor 51 in accordance with the present embodiment ispositioned outside the resolver fixing part 90 and fixed to the rotatingpart 40. The resolver rotor 51 in accordance with the present embodimentmay include a rotor body 511, an inner groove 512 and a plurality offastening holes 513.

The rotor body 511 may form a plane in a belt shape along a circular arcshape. The outside of the rotor body 511 may form a circular curvedsurface. The inner groove 512 may form a polygonal groove in the rotorbody 511.

The plurality of fastening holes 513 may be used to install a fasteningmember 514 in the rotor body 511. The fastening member 514 may be abolt. The plurality of fastening holes 513 may be formed along the rotorbody 511, and the fastening member 514 may be fixed to the mountingframe 42 through the fastening holes 513 formed in the rotor body 511.Therefore, the resolver rotor 51 may be directly mounted on the rotatingpart 40 without a separate cover part, and rotated with the rotatingpart 40.

When the resolver rotor 51 and the resolver fixing part 90 are spaced ata sufficient distance from the stator 20 to generate electromagneticwaves, the resolver rotor 51 may be directly mounted on the rotatingpart 40 without a separate cover part. When the resolver rotor 51 andthe resolver fixing part 90 are installed close to the drive shaft 110serving as a motor rotating shaft, the influence of electromagneticnoise may be limited. Therefore, the resolver rotor 51 may be directlyfastened to the rotating part 40 or the drive shaft 110.

FIG. 8 is a perspective view illustrating that a resolver rotor inaccordance with another embodiment of the present invention has mountinggrooves.

As illustrated in FIGS. 4 and 8, the resolver rotor 51 in accordancewith the present embodiment may include a rotor body 516, an innergroove 517 and a plurality of mounting grooves 518.

The rotor body 516 may form a plane in a belt shape along a circular arcshape. The outside of the rotor body 516 may form a circular curvedsurface. The inner groove 517 may form a polygonal groove in the rotorbody 516.

The plurality of mounting grooves 518 may be formed along the outercircumference of the rotor body 516. The plurality of mounting grooves518 may be installed at preset intervals on the outer circumference ofthe rotor body 516. Therefore, separate protrusions 421 formed on themounting frame 42 of the rotating part 40 may be inserted into themounting grooves 518. Thus, the resolver rotor 51 may be directlymounted on the rotating part 40 without a separate cover part, androtated with the rotating part 40.

As described above, the first and second covers 53 and 56 may beinjection-molded as separate products and coupled to the resolver rotor51. Thus, since the resolver rotor 51 can be used in common, themanufacturing cost can be reduced.

Furthermore, since the resolver rotor 51 is directly fixed to therotating part 40 without a separate cover part, the space can beutilized more efficiently.

Furthermore, since the rotor 51 or the resolver moving part 60 and theresolver fixing part 90 for measuring the rotation of the rotor 30 areinstalled in the stator 20, the installation space of the gear shiftpart 100 for changing the output of the rotating part 40 can be secured,which makes it possible to improve the power of the vehicle.

Although exemplary embodiments of the invention have been disclosed forillustrative purposes, those skilled in the art will appreciate thatvarious modifications, additions and substitutions are possible, withoutdeparting from the scope and spirit of the invention as defined in theaccompanying claims.

What is claimed is:
 1. An in-wheel working device comprising: a statorfixed to the inside of a housing; a rotor rotatably installed in thestator; a rotating part rotatably installed in the housing, the rotatingpart being configured to be rotated with the rotor; a resolver fixingpart fixed to the inside of the housing; and a resolver moving partcomprising: a resolver rotor positioned outside the resolver fixing partfacing the resolver fixing part; and a cover part fixed to the rotatingpart and covering the resolver rotor.
 2. The in-wheel working device ofclaim 1, wherein the cover part is injection-molded in a shape to coverthe resolver rotor.
 3. The in-wheel working device of claim 2, whereinthe rotating part comprises: a mounting frame installed in a shape tocover the rotor; and a motor shaft connected to the mounting frame,having a hollow portion formed therein, and rotatably installed in thehousing.
 4. The in-wheel working device of claim 3, wherein the coverpart is fixed to the mounting frame and has a larger inner diameter thanan outer diameter of the resolver fixing part.
 5. The in-wheel workingdevice of claim 3, further comprising: a gear shift part configured toshift gears using power received from the motor shaft; and a drive shaftpassing through the inside of the motor shaft, and configured to berotated by power received from the gear shift part.
 6. The in-wheelworking device of claim 1, wherein the cover part comprises: a firstcover installed in a shape to cover a first side of the resolver rotor;and a second cover installed in a shape to cover a second side of theresolver rotor opposite the first side.
 7. The in-wheel working deviceof claim 6, wherein the first cover comprises: a first base forming aplane in a circular arc shape at a position facing the first side of theresolver rotor; a first inner member extended from the innercircumference of the first base toward the second cover; and a firstouter member extended from the outer circumference of the first basetoward the second cover.
 8. The in-wheel working device of claim 6,wherein the second cover comprises: a second base forming a plane in acircular arc shape at a position facing the second side of the resolverrotor; a second inner member extended from the inner circumference ofthe second base toward the first cover; and a second outer memberextended from the outer circumference of the second base toward thefirst cover.
 9. An in-wheel working device comprising: a stator fixed tothe inside of a housing; a rotor rotatably installed in the stator; arotating part rotatably installed in the housing, the rotating partbeing configured to be rotated with the rotor; a resolver fixing partfixed to the inside of the housing; and a resolver rotor positionedoutside the resolver fixing part facing the resolver fixing part,wherein the resolver rotor is fixed to the rotating part, configured tobe rotated with the rotating part, and implemented with a single member.10. The in-wheel working device of claim 9, wherein the resolver rotorcomprises: a rotor body forming a plane in a belt shape along a circulararc shape; and an inner groove forming a polygonal groove in the rotorbody.
 11. The in-wheel working device of claim 10, wherein the rotatingpart comprises: a mounting frame installed in a shape to cover therotor; and a motor shaft connected to the mounting frame, having ahollow portion formed therein, and rotatably installed in the housing.12. The in-wheel working device of claim 11, wherein the rotor body isfixed to the mounting frame by a fastening member.
 13. The in-wheelworking device of claim 11, wherein the rotor body has a plurality ofmounting grooves formed along the outer circumference thereof, and themounting grooves are directly mounted on the mounting frame.